Fire Protection Equipment

A dust explosion or fire can occur where pneumatic conveying and dust filtration systems are combined with manufacturing processes. A spark can occur along the production line where the air system can pick it up and transport it along with highly combustible materials. When the spark reaches the filter, dust collector or storage bin, a dust explosion or fire is possible.

Spark Detection and Extinguishing Systems

Spark Detection and Extinguishing Systems have been recognized in many industries as the most cost effective and safest way to protect workers, plant and equipment from fires or explosions due to sparks entering pneumatic dust conveying and collection systems.

Rees-Memphis typically uses systems from FLAMEX, Inc., an award winning leader in fire protection technology. FLAMEX systems detect and extinguish sparks in an average of less than 3/10 of a second, well before it reaches a filter or collection bin. As a spark travels through the duct work, it is instantly identified by infrared detectors flush mounted to the duct wall. A signal releases water–flow through nozzles placed strategically where an instantaneous wall of water effectively extinguishes the spark. The system then resets itself with no down time or clean-up.

Abort Gates

High speed abort gates are designed to divert hazardous conditions due to fire or explosion out of pneumatic dust conveying systems and away from plant facilities and dust collection equipment. Rees-Memphis provides abort gates and support stands which are placed in front of an inlet to a filter or in the return air duct going back into the building.

Gates are held open by a DC magnet and activated by a signal from the spark detection system. In 500 milliseconds, the gate closes, diverting the hazard to atmosphere. Abort gates can be installed in duct sizes from 4” diameter to 60” diameter, are available with a manual or powered reset, and include open/closed indicators and controls.

Back-Draft Dampers

REES Back-Draft Dampers are installed at filter inlets using counter weights and explosion relief panels to prevent air flow from traveling back into the plant on the suction side of the duct system. During normal operation, the dust conveying air keeps the damper blade open. When an explosion occurs, the air flow reverses back through the damper through the relief panel to atmosphere.

Explosion Vents

REES uses low pressure explosion vents in dust filters, cyclones, storage bins, and ductwork to provide a relief point in the system for air to escape in the event of an explosion. Explosion panels are installed with enough pressure to withstand the normal system pressure during operation. If an explosion occurs, the panels blow out and relieve the pressure that would otherwise damage dust collection equipment, duct system components, or production equipment.

Deluge Systems

Another way to reduce the risk of fire damage is through the use of water systems that deluge the dust collection equipment with a massive flow of water. Special precautions should be taken to allow for water to escape the equipment and for maintenance crews to have easy clean-up access.